Lemes Júlia Borges Paes, de Campos Lima Tais, Santos Débora Oliveira, Neves Amanda Ferreira, de Oliveira Fernando Silva, Parada Carlos Almicar, da Cruz Lotufo Celina Monteiro
Department of Physiological Science, Universidade Federal de Uberlândia, Minas Gerais, Brazil.
Department of Physiological Science, Universidade Federal de Uberlândia, Minas Gerais, Brazil.
Neurosci Lett. 2018 May 29;676:8-12. doi: 10.1016/j.neulet.2018.04.003. Epub 2018 Apr 4.
At dorsal root ganglia, neurons and satellite glial cells (SGC) can communicate through ATP release and P2X7 receptor activation. SGCs are also interconnected by gap junctions and have been previously implicated in modulating inflammatory and chronic pain.We now present evidence that SGCs are also involved in processing acute nociception in rat dorsal root ganglia. Using primary dorsal root ganglia cultures we observed that calcium transients induced in neurons by capsaicin administration were followed by satellite glial cells activation. Only satellite glial cells response was reduced by administration of the P2X7 receptor antagonist A740003. In vivo, acute nociception induced by intraplantar injection of capsaicin in rats was inhibited by A740003 or by the gap junction blocker carbenoxolone administered at the dorsal root ganglia (L5 level). Both drugs also reduced the second phase of the formalin test. These results suggest that communication between neurons and satellite glial cells is not only involved in inflammatory or pathological pain, but also in the transmission of the nociceptive signal, possibly in situations involving C-fiber activation.
在背根神经节中，神经元与卫星神经胶质细胞（SGC）可通过三磷酸腺苷（ATP）释放和P2X7受体激活进行通信。卫星神经胶质细胞也通过缝隙连接相互连接，并且先前已被证明与调节炎症性疼痛和慢性疼痛有关。我们现在提供证据表明，卫星神经胶质细胞也参与大鼠背根神经节中急性伤害性感受的处理。使用原代背根神经节培养物，我们观察到辣椒素给药诱导的神经元钙瞬变之后是卫星神经胶质细胞的激活。仅通过给予P2X7受体拮抗剂A740003可降低卫星神经胶质细胞的反应。在体内，大鼠足底注射辣椒素诱导的急性伤害性感受可被A740003或在背根神经节（L5水平）给予的缝隙连接阻滞剂羧苄青霉素抑制。这两种药物还可减轻福尔马林试验的第二阶段。这些结果表明，神经元与卫星神经胶质细胞之间的通信不仅参与炎症性或病理性疼痛，还参与伤害性信号的传递，可能在涉及C纤维激活的情况下也是如此。
